Variable delivery oscillating piston machine



June 29, 1954 E, Buss 2,682,230

VARIABLE DELIVERY OSCILLATING PISTON MACHINE Filed F610.` 20, 1951 3 ShEetS-Sheet l E. Buss4 June 29, 1954 VARIABLE DELIVERY OSCILLATING PISTON MACHINE Filed Feb. 20, 1951 5 Sheets-Sheet 2 INVENToR. eA/6r 5055 BW June 29, 1954 E. BUSS VARIABLE DELIVERY OSCILLATING PISTN MACHINE Filed Feb. 20, 1951 I5 Sheets-Sheet 3 INVENTOR. Z/V 5099 Patented June 29, 1954 UNITED STATES PATENT OFFICE VARIABLE DELIVERY OSCILLATING PISTON MACHINE 13 Claims.

This invention relates to fluid machines and, more particularly, to an improved variable delivery machine wherein concentrically rotating members are given an oscillating movement with respect to each other While rotating, so that strokes are effected by piston elements in the oscillating members. The machine of the present invention can function as a pump, engine, or compressor, and for convenience will be described as a pump.

In a machine constructed in accordance with the present invention, the two concentrically rotating piston members are driven through a third rotating member which is mounted on an offset axis parallel to the common axis of the two piston members. The motion transmitting means from this third member in devices previously known have involved a relatively large number of moving parts requiring a high degree of accuracy of fit, together with relatively complicated assembly procedures. It is an object of the present invention to provide a machine of the class described having much simpler driver connecting means between the third, offset, member and the two concentric piston members. It is a further object to provide simple adjusting means for Varying the amount of offset of the third member axis, so that the oscillating piston stroke may be readily changed by hand, only, while the machine is operating.

Another object of this invention is to provide a fluid machine of the above-mentioned type which will operate equally well in either direction of rotation, using the same inlet and outlet connections for either direction.

A further object of the present invention is to provide a fluid machine having an eccentrically positioned rotating member, wherein all parts are in balance in operation and produce no vibration, dynamic shaking, or wobbling forces when rotating.

It is still another important object of the present invention to provide a rotary fluid machine having two oscillating piston members with greatly simplified piston and displacement chamber construction wherein each such member is an integral unit having no relatively moving parts, and wherein the actual operation is accomplished by these two integral members alone.

Further objects and features of advantage will be noted in the detailed description of a preferred embodiment, to follow.

Briey, my invention comprises a pair of almost identical concentrically rotating piston members, these members being of equal outside CII.

diameter, and each having radially arranged projections spaced by an equal number of radially arranged depressions, these projections and depressions being in one side only, of each member. The pair fit adjacent to each other on a common shaft, with the outer surfaces of the projections of one exactly mating with the bottoms of the depressions of the other, and vice versa.` The proportions of the projections, or

' pistons, are such that, when the members are faced together in operating position, a predetermined amount of relative oscillation therebetween is enabled.

A driver pin is attached to each rotative member, the two pins extending axially, as will be hereinafter described, from one side of the assembly to be driven as cranks by a third rotating member. The third member rotates on a separate axis offset from the common center line of the piston members, and carries bearing sockets for receiving and driving the driver pins. Radial ways are provided for carrying the bearing sockets so that they may move in and out from the center of the third member as required.

The axis of the third member is supported eccentrically of the common shaft of the piston members. Hand lever means are provided to move the rotational center line of the third member into or out of coincidence a desired amount from the rotational center of the piston members.

Combination inlet and outlet ports are provided in the rims of the piston members in communication with the fluid chambers formed between the piston projections, and stationary manifolds for admitting and discharging fluid from the ports surround the rims of the piston members over the rotating paths of the ports. The manifolds are linked by appropriate check valves and piping to inlet and outlet connections for the pump. The machine may be driven by applying rotational motion through any one of the three rotatable members or power taken therefrom. Alternately, the inlet and outlet ports may lead from the fluid chambers to the center of the pump assembly where they communicate with passages through the center of the shaft about which the piston members are mounted. In this event, the exterior manifolds are not required, and the inlet and outlet connections are made to the shaft interior.

This invention will be more fully understood by reference to the accompanying drawings, shown by way of illustration and not limitation, of specific apparatus embodying the invention. In the drawings:

aeeaaao Figure 1 is a side elevation view of a complete pump, showing one type of fluid manifold partly in sectional form and partly cut away to show the exterior of the two piston members.

Figure 2 is an end elevation of the pump viewed as indicated by the line 2-2 in Figure 1.

Figure 3 is another end elevation viewed as indicated by the line 3-3 in Figure l.

Figure 4 is a perspective view of one of the piston members, showing its internal construction and port location.

Figure 5 is a perspective view of the other piston member, similar to Figure 4.

Figure 6 is an enlarged sectional view of the pump assembly portion indicated by the boundary line E in Figure 1, showing the manifold f1tting and inner seal between the piston members.

Figure '7 is a longitudinal sectional view of a partial pump assembly of the present invention, showing an alternate port and manifold arrangement.

Referring irst to Figures 1, 2, and 3 for a detailed description of specific apparatus embodying my invention, there is a base plate I supporting two end supports 2 and 3 bolted or otherwise removably attached thereto. The left support 2 is bored to hold a stationary shaft 4 and the right support 3 is bored to hold an offset shaft 5. The bore center for the offset shaft 5 is in a vertical plane with the bore for the stationary shaft 4 but slightly lower, as shown. by dimension A. A set screw 6 is provided in the top of the left support 2 to clamp the stationary shaft 4, and a similar screw is located in the right support 3, preferably with a finger-operated head 'I to aid in changing the angular position of the oifset shaft 5 as desired. The purpose of this movement is to vary the volume of the pump displacement per revolution, as will be described later.

At the inner end of the offset shaft 5, an eccentric stub 8 is formed, having a stub center line 9. A connecting pin II) is provided in holes in the inner ends of the stationary shaft 4 and stub 8, to act as a solid joint between the two shafts when the shafts are clamped in the end supports 2 and 3. The center of the connecting pin I is located an equal distance from the center of the stationary shaft 4 and the stub center line 9, respectively, and is co-linear with the bore center in the right support 3. Thus, when the offset shaft is turned in the right support 3, the stub 8 varies from a position concentric with the stationary shaft 4 to a maximum offcenter position as illustrated in Figure 1.

A first piston housing II and a second piston housing I2 are rotatably mounted on the stationary shaft 4 by means of two tapered roller bearings I4 fitting against the outer side of each housing. At the inner sides, the piston housings II and I2 rest against each other along fluid tight surfaces, formed as follows.

As shown in Figures 4 and 5, each piston housing comprises an outer rim I5 of substantially annular shape. Inside of the outer rim, one side of the housing is channeled out in a large V-section fluid groove I6 surrounding a central hub I1. The end of this hub I'I lies flush with the side of the outer rim I5. The rst piston housing II has a hub sleeve I9 attached thereto which slides within the hub of the second piston housing I2. An O-ring hubseal 2l!y is installed around the hub sleeve I9 and bears between this sleeve and the interior of the hub of. the second piston housing I2.

On opposite sides of the hub I`I, two fluid pistons 2I are attached in the fluid groofve I6. These pistons are shaped to t tightly against the sides of the groove along the full slope of the sides thereof, and also shaped to mate exactly with the sides of the fluid groove in the other piston housing when the two housings are brought into adjacent relationship. In this manner, two pistons in each housing are positioned alternately with respect to the two pistons of the other housing around the periphery of the hubs Il in the assembled pump. Each piston 2| extends circumferentially for approximately 671/3, so that one housing can rotate 45 relative to the other before the flat piston ends 22 come into contact. Thus, four fluid chambers are formed, two closing simultaneously with the opening of the other two when relative housing rotation occurs. The fluid chambers lie in a toroid-like path having a square or diamond-shaped cross section.

The first piston housing II contains an arcuate slot 24 in the outer rim I5. Halfway around the rim from the slot 24 is av short driver pin 25 threaded tightly into the rim and projecting out parallel to the axis of rotation of the housing. The second piston housing I2 carries a long driver pin 26 threaded into a pin hole 28 in the rim thereof, as best shown in Figure 6, and projecting in the same direction as the short driver pin 25 when the parts are assembled. The two driver pins 25 and 26 and the arcuate slot 24 are all located at equal radial distances from the center of rotation. with the long driver pin extending through the arcuate slot 24 and relatively positioned so that full reciprocal motion of the piston housings I I and I2 is permitted with the long driver pin 26 moving from end to end of the arcuate slot 24. The external ends of the driver pins are at the same distance fromv the first piston housing II.

A driver wheel 2'I is rotatably mounted, by a ball bearing assembly 29, on the stub 8 concentric with the stub center line 9. On the side toward the piston housings, the driver wheel 2'I carries a pair of parallel guide bars 39 chordwise thereof at equal distance from the stub center line. A cylindrical driver bearing 3I is mounted on the end of each driver pin 25 and 25, and the outside of each driver bearing 3I fits between the guide bars 30 on opposite sides of the stub center line 9. The driver pins can rotate freely in the bearings 3| and the bearings can roll or slide freely in radial directions between the guide bars 30 as the pump rotates.

It is thus seen that when the driver wheel 21 rotates, it drives the piston housings II and I2 by their respective driver pins 25 and 26'. If the offset shaft 5 is held in a position where the stub center line 9 is coincident with the center of the stationary shaft 4, the piston housings I I and I2 will be driven at equal speeds with no radial movement of the driver bearings SI, and no relative rotation between the housings. Consequently, there is no relative piston movement, and no pumping action can occur.

However, if the finger head 'I set screw is loosened and the offset shaft 5 rotated a few dcgrees by means of a hand lever 32 (Figure 3.) secured tothe offset shaft 5 or eccentric stub 8 to a new position and then tightened again, the stub center line` 9 is rotated out of coincidence with the stationary shaft 4. As a result, the effective crankv radius of one driver pin continually changes with respect to that of the other driverY pin, as the driver wheel 21 revolves, and an-oscillatory motion of the piston housings i II `and I2 is added to their rotary motion.- During changing of the offset shaft position, the stub 8 merely rotates around the connecting pin I0, or the connecting pin I can be rotatable within the stationary shaft 4. The position shown in Figure 1 is the one where maximum reciprocation of the housings occurs.

The driver wheel 21, having a steady speed at all times, may have gear teeth 34 on its rim, and be externally driven by a driving gear `35, as shown or be designed for a belt drive or the like. The tapered roller bearings M are preferably held forced toward each other, such as between the guide bars 30 or a collar fixed to the end of the stationary shaft 4 and an adjustable compression spring 35 surrounding the stationary shaft 4. In this manner, the piston housings I-I and I2 can be held together with any desired force. A piston ring type seal 31 (Figure 6) is provided between the housings I I and I2 in housing grooves 39 in the outer rim I5.

For the pumping operation, two opposite ports 40 are provided in the first piston housing II, these ports 4U leading through the outerrim I5 from two opposite fluid chambers within the pump (immediately adjacent a piston) to the exterior, and two similar ports 40a are provided in the second piston housing I2 for the other two fluid chambers. Two separate stationary manifolds 4I and 42 encircle the outer rims of the piston housings II and I2, respectively, in communication with. the ports IU and 40a respectively, with running seals M to prevent leakage of fluid from the manifolds. The manifolds 4I and 42 are split on one side, for installation purposes, and are held together at these splits by clamp bolts 45 through opposite clamp ears 56. Each manifold has a lower fluid connection to one of two pipes 41 which adjustably support the manifolds and restrain them from rotation by means of a removable mounting strip i9 in the base plate I.

Connected to the two pipes 41 are two pump lines 50 and 5I, each of which intersects one of two supply lines 52 and '53 at Ts. One supply line 52 contains two check valves 55 and 55a, one on each side of the T connection, with their free ow directions being in the same direction along the supply line 52. Likewise, the other supply line 53 contains two other check valves 55h and 55o, similarly located and arranged.

On the opposite side of check valves 55a and 55C from the pump lines 50 and 5I, the supply lines 52 and 53 merge into an inlet line 56. Similarly, on the far side of check valves 55 and 55h from the pump lines, the supply lines 52 and 53 merge into an outlet line l. It is thus seen that free now is allowed from the inlet line 56 through both supply lines 52 and 53, to the outlet line 51.

As referred to previously, during rotation of the pump for one-half revolution of the driving wheel 21, two of the four uid chambers are being closed while the other two are being opened. During the following one-half revolution, the opposite condition prevails, to open the first mentioned two chambers and close the second two chambers. This means that each of the pump lines 5I] and 5I alternately serves as an intake and exhaust line during each whole revolution 6 tion of the pump draws fluid from the inlet line 5B and forces it out at the outlet line 51.

Referring to Figure 7, the pump porting can be accomplished through a hollow stationary shaft 4a rather than through the external manifolds 4I and 42. This hollow shaft 4a extends from the left end support 2 to a location on the left of the connecting pin I0, which remains solid to support the two shafts of the pump. Within the hub I1 of the rst alternate piston housing IIa, a series of right-hand ports 60 is drilled through the hollow shaft 4a, and within the hub of the second alternate piston housing I2a is a similar series of left-hand ports 6I. A flanged tube 62, inserted from the left end of the hollow shaft, separates the right-hand ports 60, which communicate with the inside of the tube 62, from the left-hand ports 6I, which communicate vwith the annular portion of the hollow shaft interior around the tube. I

In the alternate piston housings Ila and I2a. of Figure 7, an internal flange 64 on each housing rides on the hollow shaft 4err and each mounts an end seal 65. At the junction of the two housings at the inner edges, a shaft collar 66 effectively seals off the right-hand ports 60 from the left-hand ports 6I. This collar may be an integral port of one of the piston housings, if desired. In the first alternate piston housing IIa, two oppositely directed passages 61 connect the right-hand ports G with two opposite fluid chambers in the pump assembly. These passages v61 are also shown in phantom lines in Figure 4, it being understood that they are used in the alternate configuration of Figure 7 only, with the two rim ports 40 being omitted. Likewise, two additional oppositely directed passages 69 (Fig-` ure 5) in the second alternate piston housing |20, connect the left-hand ports 6I with the remaining two pump fluid chambers.

Toward the left end of the hollow shaft 4a, two line connections 10 and 1I are made to the end of the tube 62 and the shaft interior, respectively. These line connections 10 and 1I T into two supply lines 52a and 53a similar to the plumbing of the rst embodiment in Figure l. The remainder of the piping in Figure '7 is identical to that already described.

Other porting arrangements can be employed using the same type piston housings and oscillating driving means of the present invention. Automatic valving means may also be incorporated if desired. While a pump unit with four piston elements has been shown and described herein, the invention is not limited to this nurn-- ber, since the construction can be adapted to a different number without changing the essence of the invention.

It is thus seen that a very simple piston construction and driving means for the oscillating movement have been provided. This pump will operate with the same inlet and outlet connections whether the rotary motion is in one direction or the other. The piston stroke can be easily changed between zero and maximum While the pump is in operation, merely by loosening the set screw of the offset shaft 5 and rotating the hand lever 32.

From the above description it will be apparent that there is thus provided a device of the character described possessing the particular features of advantage before enumerated as de sirable, but which obviously is susceptible of modification in its form, proportions, detail construction and arrangement of parts without departing from the principle involved or sacrificing any of its advantages.

While in order to comply with the statute, the invention has been described in language more or less specific as to structural features, it is to be understood that the invention is not limited to the specific features shown, but that the means and construction herein disclosed comprise the preferred form of several modes of putting the invention into effect, and the invention is, therefore, claimed in any of its forms or modifications within the legitimate and valid scope of the appended claims.

I claim: i

1. In a rotary fluid machine, the combination of a stationary mounting shaft, a pair of piston housings rotatably mounted on said mounting shaft, each of said piston housings having on one side thereof an annular rim and a hub section, the ends of said hubs lying flush with the sides of said rims in each respective housing, fixed projections between said rim and said hub arranged around the center of rotation of said housing and spaced by inwardly extending depressions having a greater total arcuate length than the total arcuate length of said projections, to form a plurality of uid chambers in said housings, the depth of said depressions in an axial direction from said rim equalling the axial height of said projections from said rim in the opposite direction, said projections and depressions in both housings having similar mating end shapes so that the projections of each housing just mate with the depressions of the other housing and so that a maximum percentage volume is displaced during maximum relative rotation of said housings when brought rm-to-rim, and rotary driving means connected to said housings i'or rotation and relative oscillation thereof.

2. Apparatus in accordance with claim l wherein said driving means comprises an offset axle adjacent one end of said mounting shaft, said axle having a center line parallel to the extended axis of rotation of said piston housings, a driving wheel rotatably mounted on said offset axle, guide channel means extending diametrically on the side of said driving wheel toward said piston housings, a first driver member attached rigidly to one housing, said first driver member extending externally and having bearing means on the external end to mate with said guide channel means, a second driver member attached rigidly to the other housing, said second driver member extending past said first housing and having additional bearing means on the external end to mate with said guide channel means on the opposite side of said center line from said first driver member, said driver members being slidable radially of said driving wheel in said guide channel means and constrained to be driven in a circular direction in said bearing means by said channel means, said driving wheel adapted to be rotated by external driving means.

3. In a rotary fluid machine, the combination of a stationary mounting shaft, a pair of piston housings rotatably mounted on said mounting shaft, said housings having piston members and chambers therein arranged to give double-acting pumping strokes as said housings are oscillated back and forth with respect to each other around said mounting shaft, an offset axle adjacent one end of said mounting shaft, said axle having a center line parallel to the extended axis of rotationof said piston housings, a driving wheel rotatably mounted on said offset axle, guide means extending diametrically on the side of said driving Wheel toward said piston housings, a rst driver member attached rigidly to one housing and extending externally to mate with said guide means, and a second driver member attached rigidly to the other housing and extending past said first housing to mate with said guide means on the opposite side of said center line from said first driver member, said driver members being slidable radially of said driving wheel in said guide means and constrained to be rotatively driven by said guide means, and said driving wheel adapted to be rotated by external driving means.

4. Apparatus in accordance with claim 3 including adjustable stroke displacement means comprising an eccentric hub on said offset axle, said driving wheel being rotatable about the center of said hub, and means for shifting the angular position of said oiset axle around said axle center line, whereby the center of rotation of said driving wheel is changed relative to the center of rotation of said piston housings.`

5. Apparatus in accordance with claim 3 wherein an eccentric hub is provided on said offset axle adjacent to said one end of said mounting shaft, said driving wheel being rotatable about the center of said hub, and including adjustable stroke displacement means comprising a connecting pin extending from said hub into said stationary mounting shaft along said axle center line, means for clamping said offset axle in any position of revolution, and manuallever means attached to said axle to rotate said axle about said axle center line and about said connecting pin to any position in a range of substantially degrees, whereby the displacement per revolution can be altered from zero to maximum while said machine is operating.

6. In a rotary fluid machine having two rotatable members adapted to be'relatively oscillated in a rotary direction, an improved pumping arrangement wherein each of said rotatable members comprises a piston housing having an annular rim and a hub portion on one side thereof positioned to substantially abut the rim and hub portion, respectively, of the other housing when mounted concentrically, xed projections extending outwardly from said one side between said rim and said hub arranged around the center of rotation of said housing and spaced by inwardly extending depressions having a greater total arcuate length than the total arcuate length of said projections, said projections being segments of a toroid-like body having a triangular cross section, and said depressions being spaces exactly mating with an inverted projection so that the apexes of each projection are slidable along the bottoms of the respective depressions in the other housing when said housings are in abutting position, said projections and depressions in both housings having coincident end surfaces so that a maximum percentage volume is displaced during maximum relative rotation of said housings.

7. Apparatus in accordance with claim 6 wherein said piston housings are mounted on a stationary mounting shaft, and including driving means which comprises an offset axle adjacent one end of said mounting shaft, said axle having a center line parallel to the extended axis of rotation of said piston housings, a driving wheel rotatably mounted on said offset axle, guide means extending diametrically on the side of said driving wheel toward said piston housings, a first driver member attached rigidly to one housing and extending externally to mate with said guide means, and a second driver member attached rigidly to the other housing and extending past said first housing to mate with said guide means on the opposite side of said center line from said first driver member, said driver members being slidable radially of said driving wheel in said guide means and constrained to be rotatively driven by said guide means, and said driving Wheel adapted to be rotated by external driving means.

8. Apparatus in accordance with claim 1 in cluding axially adjustable compression means carried by said mounting shaft for holding said piston housings forced together.

9. Apparatus in accordance with claim 1 including a first plural-ity of port passages in one of said housings leading from the outer circumference thereof inwardly to intersect eachalternate one of said fluid chambers formed by said housings when assembled, a second plurality of port passages in the other housing leading from the outer circumference thereof inwardly to intersect the remaining alternate fluid chambers, stationary manifold means surrounding the circumference of each of said housings in communication with said first and second plurality of port passages, respectively, a fluid connection into each of said manifold means from the outside thereof, a machine inlet port, a machine outlet port, and valving means connected between said machine ports and said fluid connections whereby fluid from said inlet port is drawn into said fluid chambers and discharged therefrom into said outlet port during each revolution of said piston housings.

l0. Apparatus in accordance with claim 1 including a nrst plurality of ports in one of said housings leading from the interior of the hub thereof outwardly to intersect each alternate one of said uid chambers formed by said housings when assembled, a second plurality of ports in the other housing leading from the interior of the hub thereof outwardly to intersect the remaining alternate uid chambers, two separate fluid passages within said stationary mounting shaft, means communicating each of said fluid passages respectively with each of said pluralities of ports, a machine inlet port, a machine outlet port, and valving means connected between said machine ports and said uid passages whereby fluid from said inlet port is drawn into said uid chambers and discharged therefrom into said outlet port during each revolution of said piston housings.

11. Apparatus in accordance with claim 1 including a rst plurality of ports in one of said housings leading from the interior of thehub thereof outwardly to intersect each alternate one of said fluid chambers formed by said housings when assembled, a second plurality of ports in the other housing leading from the interior of the hub thereof outwardly to intersect the remaining alternate fluid chambers, means delining a separate annular collecting space between each housing hub and said mounting shaft, fiuid passages connecting each of said collecting spaces with separate portions of the interior of said mounting shaft, a machine inlet port, a machine outlet port, and valving means connecting said machine ports through said shaft interior to said fluid passages whereby fluid from said inlet port is drawn into said uid chambers and discharged therefrom into said outlet port during each revolution of said piston housings.

12. Apparatus in accordance with claim 1 including a first plurality of port passages in one of said housings intersecting each alternate one of said fluid chambers formed by said housings when assembled, a second plurality of port passages n the other housing intersecting the remaining alternate fluid chambers, separate manifold means in communication with said rst and second plurality of port passages, respectively, a machine inlet port, a machine outlet port, and valving means connected between said machine ports and said manifold means whereby intake material from said inlet port is drawn into said chambers and exhaust material is discharged from said chambers into said outlet port during each revolution of said piston housings.

13. Apparatus in accordance with claim 1 including a first plurality of port passages in one of said housings intersecting each alternate one of said fluid chambers formed by said housings when assembled, a second plurality of port passages in the other housing intersecting the remaining alternate fluid chambers, separate manifold means for each said plurality of port passages, means communicating each of said manifold means respectively with said first and second pluralities of port passages, a fluid connection into each of said manifold means from the exterior thereof, a, machine inlet port, a machine outlet port, and valving means connected between said machine ports and said fluid connections whereby fluid from said inlet port is drawn into said fluid chambers and discharged therefrom into said outlet port during each revolution of said piston housings.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,313,214 Benz Mar` 9, 1943 2,426,361 Lester Aug. 26, 1947 2,453,271 Sales Nov. 9, 1948 2,553,954 Bancroft May 22, 1951 2,565,860 Lester Aug. 28, 1951 FOREIGN PATENTS Number Country Date 135,192 Great Britain 1921 548,857 Great Britain Oct. 27, 1942 

